September 2011 Fastrack

[Matt93SE]

I find this interesting, because we had a driver in the DC region who bought an ITA 240SX a couple of years ago that had been raced for a number of years with no power steering. He ran it for a season and a half that way, until someone said something about it and he re-installed the pump & lines. He's not a particularly large guy, so I can't imagine he would have continued to drive it had it been that much of a handful. Also, the car won quite a few races (back in the pre-AJ/Price days) so it didn't seem to make too much difference.

If that guy reinstalled the pump and lines and still "didn't have power steering", then he either had an upper body like The Hulk, or he wasn't putting fluid back in the system so the pump freewheeled with no fluid to pump.

The pump itself is indeed a sliding vane type.

that said, I really wasn't opposed to how the factory power steering system felt when it worked. It was a matter of reliability and weight for me. I've stripped just about everything I can out of the car according to the rules, running 13lb wheels with nearly bald tires, empty fuel tank, and I'm STILL 50lb over... but I digress..

ok - that's good info, and corrects my earlier statements. What I really want to know is about your success with underdriving as a means to reduce shaft RPM and power loss, and to improve reliability. have you? to what degree? and fwiw I know hondas and at least some mazdas work just fine with the PS belt cut.

I've run an underdrive crank pulley on my 240 and Maxima for years. The Max would run out of power assist even pulling into a parking lot or during a slalom autoX. It would work fine the first direction, but the second you'd turn the wheel the opposite direction, you'd have about 1/2 second of *ohsh!t* with no steering, then it'd work again. So for a slalom you had to be very gentle with the steering.
on the road course, the car was fine though since steering inputs are smaller, slower, and engine rpm was almost always above 4500.

As for the 240, I don't ever recall having issues with it running out of power assist mid-maneuver, or with a lack of steering feel like my current G35 daily. (I took it to the track once and OMG the steering is numb on that thing compared to either the Maxima or the 240!) I run/ran an underdrive crank pulley but stock power steering and water pump pulley--the S14 chassis shares the belt for water pump and power steering, not sure about the S13.

I noticed a pretty obvious difference in acceleration due to one less chunk of parasitic drag and rotating mass. Probably not a ton of horsepower gained, but throttle response was dramatically increased by the pulley change and by removing the power steering.

Pulling that pump also allows much less tension on the belt since it's only driving the water pump. I can run the belt about 1/4 of the previous required tension, and have even seen something as simple as belt tension show on a dyno plot before so the additional parasitic loss can be fairly dramatic if you're enthusiastic about cranking belts down until they almost snap.